As smaller transistors are manufactured, the critical dimension (CD) or resolution of patterned features is becoming more challenging to produce. Self-aligned patterning needs to replace overlay-driven patterning so that cost-effective scaling can continue even after extreme ultra-violet (EUV) introduction. Patterning options that enable reduced variability, extend scaling and enhanced CD and process control are needed. Selective formation of thin films is a key step in patterning of highly scaled technology nodes.